Air-Sealing Zip Sheathing to Masonry Foundation
I am remodeling the outside of the my house. It’s a split-foyer. The Basement extends above grade and has brick siding. The first level has masonite which is what I am remodeling. I am installing Zip sheathing (there currently is no sheathing behind the masonite) and I’m curious what would be the best product to seal the zip to the brick sided basement. Fentrim or Fast Flash? Fentrim seems easier and less messy, but I’m concerned it won’t bond well to the brick. The Fast Flash seems like it would be a bit more difficult but may work better and is a more versatile product so I can use it other places if I have more than I need for sealing the sheathing to the brick.
Any thoughts would be appreciated.
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Fentrim will def. bond to any concrete or clay masonry. I've used it on both and to remove it would probably require acetone and a scraper. Just make sure the surface is dust-free, and clean. If you need another layer of assurance, there are primers you can apply to the surface to enhance the adhesion, made specifically for masonry.
https://www.siga.swiss/global_en/products/dockskin/dockskin-200
I used Siga Fentrim grey to seal the bottom of the zip sheathing to the concrete foundation. It had the added benefit of doubling as brick flashing on the brick ledge. Only negative is the tape is a bit costly.
to seal to masonry, it's pretty traditional to use sealant with backer-rod or bond-break tape. if the sealant width is 2x the depth and doesn't get adhered in the back, then it's a pretty long lasting joint on an acceptable substrate. I don't know what sealants bond to Huber--check the product data.
I would probably use the zip liquid flash as it’s designed for zip and says it bonds concrete and masonry
Fast Flash also works great for this, as does the ZIP Liquid Flash. 3M makes a rough surface masking tape which sticks well enough to brick to get a clean masked edge, which you should be overhanging with siding for direct UV protection. You really don't need much overlap onto brick or concrete with a liquid flashing product, as the bond is really tenacious and you're just air sealing.
If the sheathing is proud of the brick instead of flush, it takes some extra work to apply and tool a liquid flashing because of the jog in the materials, but it's still pretty easy
Thank you all for the advice. I ended up going with Fast Flash. It's significantly cheaper than Zip's liquid flash and seems to be an almost identical product. I decided to go this route mostly because it gives more flexibility with the amount I can buy (have to buy 80' rolls of fentrim) and I have some other areas like around the chimney that are not completely straight and would be very difficult to tape.
That said the sheathing is proud of the brick and fast flash is proving very messy and tedious to install (although much easier than fast flash was). Fentrim would have been much quicker. Hindsight is 20/20.